Closure cap and method of making



Nov. 17, 1942. J. c. Glass GLOSURE CAP AND METHOD OF MAKING Filed Jan. 21, 1938 v-lll I n n n n l i r HIIHIV ATTORNEYS Patented Nov. 17, 1942 CLOSURE CAP AND METHOD OF MAKING John C. Gibbs, Brooklyn, N. Y., assigner to Anchor Cap & Closure Corporation, Long Island City, N. Y., a corporation of New York Application January 21, 1938, Serial No. 186,052

5 Claims.

The present invention relates to closure caps and to a method of making the same and is an improvement upon the cap and method of my Patent No. 2,089,954, for Closure cap and method of making, granted August 17, 1937.

Closure caps having threads or screw lugs formed from an inturned bead at the lower part of the skirt, as illustrated in my patent identified above, are very popular because of their attractive appearance and their ease of application and removal. In spite o1- the popularity of the closures on the part of consumers, it is diicult, in some cases, to form lugs that extend inwardly suiciently far to obtain a secure hold on the under side of the thread or lug projections on the container. As a result, the lugs on the cap may be bent out of their proper position or caused to ride over the lug or thread projections on the container. Glass containers, due to limitations in manufacture, vary in size and circularity. Certain tolerances are allowed glass manufacturers and cap companies are required to make caps which t glass containers within the prescribed tolerances. The caps must fit tight on a glass of minimum size and not be too tight on glass of maximum size. With any type 0f lug cap, it is diicult to obtain lugs which extend in sufficiently far to aord good seals throughl out the necessary range of size tolerances in the glass containers. Such diiculty is greatest with caps having lugs formed from an inturned bead.

The present invention aims to provide an improved screw closure cap of the lug or interrupted thread type having the lugs formed from anv inturned bead which extend inwardly a greater distance than heretofore and which are reinforced to prevent their riding over the threads or projection on a container, thereby to provide a cap which will take up the full range of tolerance in glass containers without impairing the seal formed thereon. The invention also aims to provide an improved method of making the closure cap.

An object o the invention is to provide an attra-:tive screw closure cap having improved conltainer engaging means.

Another object of the invention to provide an inturned bead having an improved lug construction formed therein.

Another object of the invention is to increase the strength, particularly in a radial direction, of the lugs formed from an inturned bead on a closure cap.

Another object of the invention is to buttress the lugs against movement in an outwardly rahlo dial direction by forming a reinforcement in the skirt of the cap back of the lugs.

Another object of the invention is to increase the inward projection of the lugs by the inward' displacement of the metal in the skirt of the cap` back of the lugs.

' Another object of the invention is to increase the effective inward' projection of the lug on a closure cap. Y

Another object of the invention is to provide an improved method of making closure caps having lugs formed from an inturned bead.

Another object of the invention is to provide a method adapted to be carried out with simple inexpensive machinery.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.

.A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawing, forming a part of the specification, wherein:

1 is a side elevational View, partly in section, of a closure'cap applied' to a container illustrating a preferred embodiment of the invention;

Fig. 2 is a fragmentary sectional View showing blank which illustrates the iirst step in the preferred method of making a closure cap;

Fig. 3 is a fragmentary sectional view similar to Fig. 2. illustrating the second step in the meth'- od of manufacturing the closure cap;

4' is a fragmentary sectionalview illustrating the third step in the preferred method of making the closure cap;

Figs. 5 and 5arare fragmentary sectional views through the skirt of the cap intermediate the lugs and through the skirt of the cap at the lugs, respectively, illustrating the fourth step in the preferred method of making the cap;

Fig. 6 is an enlarged fragmentary sectional View through the lug of the cap, illustrating the vfifth and final step in the preferred method o'f manufacturing the cap and also illustrating the details of the finished cap;

Fig. '7 is a sectional View along the line T-'I of Figs. 1 and 6, illustrating further details of the lug construction; and

Fig. 8 is a side elevational view, partly in section, illustrating another embodiment of the invention.

Referring again to the drawing illustrating the preferred embodiment of the invention, and more particularly to Fig. 1 thereof, there is shown a glass container I having thread projections or container lugs 2 thereon adapted t0 cooperate with suitable lugs 4 on a closure cap 5. The closure cap 5 has a cover portion I and a depending skirt 9, shown telescoped over the container with a sealing liner 6 intermediate the rim of the container and the cover part of the cap. The lugs 4 are formed at the lower edge of the cap and engage with the container threads or lugs 2 to hold the cap in position on the container. The lugs 4 are preferably formed from an inturned wire or beaded edge IIB which is buttressed by a projection I6, as will be described in detail hereinafter.

The preferred method of forming the closure cap is illustrated more particularly in Figs. 2 to 7. A cup-shaped blank, as illustrated in Fig. 2, is stamped from a plain, coated or lithographed sheet of metal such as tin plate. Thereafter. the lower edge of the cap is bent inwardly, as shown at I1 in Fig. 3, to facilitate the operation of forming an inturned wire edge or bead, shown at I in Fig. 4. The inturned wire edge may be formed in any suitable manner but, preferably, is rolled inwardly by means of a grooved chuck which engages the inwardly bent edge I'l and forces it toward the cover part of the cap, thus causing the edge to bend around in the groove of the chuck into the form illustrated in 4. Preferably, the wire edge is rolled inwardly .eufciently far so that the free edge I2 thereof is adjacent the skirt of the cap and well below the upper part of the bead.

The lugs are formed by forcing the bead outwardly and flattening it against the skirt of the cap at intervals about the skirt of the cap. as shown at I3 (Fig. 5), whereby the intermediate portions of the bead form the lugs 4 of the cap. Preferably, the lower sides of the lug portions are collapsed or flattened slightly, as shown at I4 (Fig. 5a), to force the lower edge of the cap outwardly to make the cap substantially circular at its lower edge. In order to improve the construction of the lugs by making the lugs extend further inwardly, and also to reinforce the lugs` the skirt of the cap is pressed inwardly at i5 directly back of the lugs and preferably adjacent the upper portions thereof, as shown more particularly at I6 in Figs. 6 and 7 of the drawing. Preferably, the projections IIS are shorter in length than the lugs and extend inwardly suf.-

ciently far to engage and force the upper portion I5 of the lugs further inward, whereby their inward projection is increased beyond that shown in Fig. 5.

The cross-sectional shape of the lug may be any desired form but, as illustrated in the preferred embodiment, the upper side of the lug or substantially horizontal portion I5 is adapted to engage the inwardly pressed portion I5 to come municate the pressure thereon to the innermost part of the lug. The free edge I2 of the cap preferably extends downwardly beneath the inwardly extending projection lE so that the lug is, in effect, a braced shelf affording a rela tively smooth horizontal upper surface for en gaging the under side of the thread on the container. The substantially fiat surface prevents the scratching of the glass and resulting breakage of glass threads. The projections l5 buttress the lugs to prevent radially outward movement thereof when screwed on the container and,

hence, minimize any tendency of the lugs to ride over the container threads. The depression I6 in the skirt of the cap is preferably above the lower edge of the skirt to prevent or minimize any irregularity in the contour of the skirt at the lower edge tending to mar the appearance of the cap. The depressions I6 may be made by applying pressure with any suitable tool and can be rapidly made in rolling machines. If desired, the portions of the skirt below the depressions may be supported during the formation of the depressions. Indentations placed above the lower edge of the cap do not impair the appearance of a cap, while indentations at the lower edge do. The latter make the cap look damaged.

The closure cap is illustrated as having the knurling 23 in the skirt of the cap. Such knurling facilitates gripping the cap for application to and removal from the container manually. The corrugations also facilitate correct positioning of the lugs in the cap where certain of the operations are performed in a rolling machine. It is to be clearly understood, however, that the caps may or may not have such knurling, as desired, or may have any other contour tending to facilitate gripping of the cap.

A modified form of the present closure is illustrated in Fig. 8 and may comprise a cover part I and depending skirt 9, as described in the preferred embodiment. The lugs 4 are formed from an inturned wire or beaded edge I0 substantially as shown in Fig. 5a. The increased inward projection of the lugs 4 beyond that illustrated in Fig. 5a is obtained by setting the collapsed portions of the bead IB outwardly, as shown at 2l, intermediate the lugs of the cap. The setting of these portions outwardly gives a relatively long circumferential flared portion, as Shown in Fig. 8, and intermediate substantially cylindrical portions 22 in back of the lugs which afford an attractive cap design. The cylindrical portions 22 of the skirt of the cap, which conceal the lugs, appear to be the normal portions of the skirt of the cap and the portions 2| flared outwardly appear to be decorations placed there not for utilitarian purposes but for improving the appearance of the cap. A cap of this construction and design is more pleasing to many purchasers than a plain cylindrical cap. Hence, the increased inward projection of the lugs is attained without marring the appearance of the cap. The modified construction has the advantage of an increased lug projection for engaging the skirt of the cap but does not have a buttressed lug, as illustrated more particularly in Figs. 1, 6 and 7 of the preferred embodiment. The lugs in the modified form extend inwardly further than lugs of prior caps and, therefore, attain an important advantage of the present invention and, at the same time, provide an attractive design of closure.

The closure cap is applied and removed as a screw closure. Any desired number of lugs 4 may be provided in the cap and a corresponding number in the container. In small caps, two lugs are usually provided and, in larger caps, three or four. The cap may be screwed on the container by rotating less than half a turn and may be removed by turning it substantially a quarter of a turn where a four-lug cap is used. This permits ready application and removal of the cap and the downward pull at a series of equally spaced points gives a very secure seal.

It will be seen that the present invention provides a closure cap with improved lugs formed from an inturned rolled edge commonly called a beaded or wire edge. The lugs project inwardly further than heretofore and sufficiently far to afford a secure grip on the lugs or thread projections of a glass container. By forcing the metal of the skirt of the cap inwardly against the lugs, the .lugs are forced inwardly farther and, at the same time, buttressed against outward radial forces effective on the lugs in applying the caps to glass containers. lugs will engage the threads on the container nearer the root of the thread, that is, nearer the wall of the container, which provides a more secure hold on the thread. In addition, the buttressed lug is able to withstand a much greaterv pressure in a radial direction and will not ride over the thread on the container. The construction of the lug and the depressed portion of the skirt of the cap is such that a substantially i'lat upper surface is afforded for engagement of the thread on the container, which eliminates sharp skirt of the cap. The above advantages are at tained without impairing the appearance of the cap and without increasing the cost thereof. The cap can be made by simple, inexpensive man chinery and is fully capable of withstanding any rough usage to which it may be subjected.

As various changes may be made in the form, construction and arrangement of the parts herein without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim:

1. The method of making a closure cap, which method comprises turning in the lower edge of the cap to form a beaded edge, flattening said beaded edge outwardly against the skirt of the cap at intervals to thereby provide lugs at the intermediate portions, pressing the bottom edge of the skirt outwardly at the lugs, and thereafter indenting the skirt of the cap inwardly at the lugs and above the lower edge of the cap without disturbing the circular contour of the bottom edge of the cap in said indenting operation to move said lugs inwardly and thereby increase the inward extension of the lugs with respect to the portions of the lower edge of the skirt intermediate the lugs and to buttress the inturned portion of the skirt forming the lugs.

2. The method of making a closure cap, which method comprises turning the lower edge of the cap inwardly to form a beaded edge, flattening said beaded edge outwardly against the skirt of the cap at intervals about the skirt of the cap to thereby provide lugs at the intermediate portions, pressing outwardly the bottom edge of the skirt at the lugs to make the bottom edge of the cap Such improved lli substantially circular, and thereafter forming inwardly extending projections in the skirt of the cap back of said lugs and entirely above the lower edge of the cap to reinforce said lugs and force them inwardly so as to increase the distance that the lugs extend inwardly with respect to the skirt of vthe cap without interrupting the circularity of the bottom edge of the cap.

3. The method of making a closure cap, which method comprises turning the lower edge of the cap inwardly, upwardly, outwardly and 'downwardly with respect to the normal portions of the cap skirt to form a beaded edge, collapsing said beaded edge outwardly against the skirt of the cap at intervals about the skirt of the cap to provide three thicknesses of metal therefrom and to provide screw lugs at the intermediate portions, pressing the bottom edge of the skirt outwardly at the lugs to make the contour thereof conform substantially to the contour of the intermediate portions, forcing said lugs further inwardly by forming buttressing portions in the skirt of the cap back of said lugs, without interrupting the circularity of the lower edge of the cap.

4. As an article of manufacture, a closure cap comprising a cover portion and a cylindrical depending skirt having an inturned bead at the bottom thereof, circumferential portions of said bead being flattened into a triple thickness of metal against the skirt of the -cap at spaced intervals to thereby provide tubular lugs at points intermediate the flattened portions, the bottoms of said tubular lug portions lying substantially in line with the normal portions of the cylindrical skirt so that the lower edge of the closure is substantially circular, and a plurality of inwardly extending projections in the skirt of the cap spaced upwardly from the bottom edge of the cap and in abutting relation to the upper portion of each of said lugs at the mid-portions thereof to buttress the inturned portions of the skirt forming said lugs and to prevent outward movement thereof in a radial direction.

5. As an article of manufacture, a closure cap comprising a cover portion and a cylindrical depending skirt having an inturned bead at the bot tom thereof, portions of said bead being flattened into a triple thickness of metal against the skirt of the cap at intervals to thereby provide tubular shelf-like lugs at intervals intermediate the flattened portions, the bottoms of said tubular lug portions lying substantially in line with the normal portions of the cylindrical skirt, said skirt having its free edge concealed in said bead to strengthen the lug construction, and a plurality of inwardly extending projections in the skirt of the cap spaced upwardly from the bottom of the skirt whereby the contour of the bottom of the cap skirt is substantially undisturbed and in abutting relation to each of the upper shelf-like portions of said lugs, and centrally disposed with respect to the lengths of said lugs, said projections being adapted to buttress the inturned portions of the skirt forming the tubular lugs to reinforce the lugs.

JOHN C. GIBBS. 

